Prepare for functional tests to be added.

- Move unit tests to sub directory
- Move dependency loading to bootstrap.php
Initial version of functional tests.

- Abstract base class for functional tests
- Simple base test
- Test for checking types

Break up unit and functional tests into separate PHPUnit test suites.
Only try to load schemas if the namespace is present in the WSDL.
Correct filename casing.

This should make the tests run on Linux.
Merge branch 'functional-tests'